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# Compute Choleski factorization of a Matrix in R Programming – chol() Function

chol() function in R Language is used to compute the Choleski factorization of a real symmetric positive-definite square matrix.

Syntax: chol(x, …)
Parameters:
x: an object for which a method exists. The default method applies to real symmetric, positive-definite matrices

Example 1:

## R

 `# R program to illustrate``# chol function` `# Initializing a matrix with``# 2 rows and 2 columns``x <- ``matrix``(``c``(8, 1, 1, 4), 2, 2)` `# Getting the matrix representation``x` `# Calling the chol() function``y <- ``chol``(x)` `# Getting the Choleski factorization``# of the specified matrix``y`

Output:

```     [, 1] [, 2]
[1, ]    8    1
[2, ]    1    4

[, 1]      [, 2]
[1, ] 2.828427 0.3535534
[2, ] 0.000000 1.9685020```

Example 2:

## R

 `# R program to illustrate``# chol function` `# Initializing a matrix with``# 2 rows and 2 columns``x <- ``matrix``(``c``(1, 2, 3, 4), 2, 2)` `# Getting the matrix representation``x` `# Calling the chol() function``y <- ``chol``(x)` `# Getting the Choleski factorization``# of the specified matrix``y`

Output:

```     [, 1] [, 2]
[1, ]    1    3
[2, ]    2    4

Error in chol.default(x) :
the leading minor of order 2 is not positive definite
Calls: chol -> chol.default
Execution halted```